Tracker device for automatic musical instruments.



C. S. BURTON.

TRACKER DEVICE FOB. AUTOMATIC MUSICAL INSTRUMENTS.

APPLroATIoN HLBD JUNE 24, 1912.

CHARLES sQBUnfroN, or our rsnx, rumors.;

TRACKER nevica ron summum iusmiu.. immune...

specuaamfmaarmt., Patented Feb.24,'1914.

.ippna'tion mea :une 24, 1912. serial No. 705,394.

To all who/m, it may concern:

a citizen of the United States, residin at Oak Park, in the county of Cook and tate of Illinois, have invented new and useful Improvements in Tracker Devices for Auto- -matic Musical Instruments, of which the following is a specification, reference being I another.

l ends.

It consists in the elements and features of construction shown and described as indicated in the claim-s.

In the drawings: Figure 1 is a sect-ion axial with respect to the rotatable member of the tracker at the plane 1--1 on Fig. 2 as to the left-hand portion of Fig. 1, and at the plane 1*-1 on Fig. 8 as to the righthand portion of said Fig. l. Fig. 2 -is a section .at the line 2-2 on Fig. 1. Fig. 3 is an end elevation of the device shown inv Fig. 1. Fig. et' is a front side elevation of the duct bar. Fig. 5 is a detail .front elevation of a portion` of the tracker intermediate the Fig. 6 is a detail ed e'elevation of the portion of the duct bar s own in Fig. 4. Fig. 7 is a detail plan view of the cheeks, the upper one being broken away at the end portion to showl the lower one.

The tracker device shown in the drawings comprises a rotatable member, 1, which is in the form of a screw shaft or roll; that is, it

is a cylindrical element having a deep screw screw thread comprising as many turns vas the maximum number of notes to be played plus the number of notes involved in the range of transposition contemplated. For

example, for playing eighty-eight notes with device comprising the cheeks, 3, gabove'l member, 1, for closing the air ducts as stat and Abelow''the-.rotary member, 1, and the Be 1t known that I, CHARLES S. BURTON,

duet bar, 4, which is embraced between the cheeks at the rear side of said rotary member. Therotary member, 1, has gudgeons,

l", at its opposite ends b p which it is journaled- 111 brackets, 5, w ich are mounted upon the back-board, 6, upon which the cheeks, 3, 3, are also mounted by means of their-flanged foot pieces, 3, which, for the 65 purpose of thus securing the cheeks to the ack-board are engaged at their ends behind lugs, 7, which are mounted on the backboard, 6, permitting the cheeks to slide a short distance toward and from the axis of the rotary member, I1. Said back board is apertured between the cheeks, arid through said aperture the duct bar, 4, protrudes and enters between the slight-1y converging portions, 3", of the cheeks, 3, said portions bein 75 I extended olf, from the curved portions whi seat upon the opposite sides ofthe rotar said cheeks effecting such closure to the ex?,

tent of .their curved seats respectively, f the 30 remainder of the closurebeing effected by the curved forward face of the duct bar, 4, between the cheeks. For holding the cheeks snugly against the duct bar and at the same time against the rotary member, and thereby vholding the duct barup against said rotary member, rods, 8, 8, extend longitudinally of the cheeks in the angle between their curved and converging portions, and springs, 9, g9

connect the corresponding ends of said' rods 90 at opposite ends of the rotary member. As illustrated in the drawings, the roximate edges of the cheeks at the i'orwar side are beveled to knife edges and spaced apart a distance suitable for the width in the direcand on the other two sides by the edges of the screw threads of the rotary member. 100

The knife-edged construction of the cheeks, 3, adapts the device for service with'a pneumatic yaction having minimum bleeders or leakports for its primary pneumatics.

Knife edges are not essential if the primary pneumatics are constructed to be operative with large leak ports. n

For stopping off the several 4grooves so that they may each constitute an independent air duct and not communicate with each other, the duct bar, 4, has at one longitudinal edge what may be called a comb or rack,

10, whose teeth engage the grooves of the screw -threads of the member, 1, fitting said grooves snugly so as to constitute a transverse closure of each when the comb is thus engaged. Preferably, this comb or rack 1s made of rubber, or some like material, made fast upon the lower longitudinal edge of the duct bar, so that each duct comprises a ortion of the groove extending from the ri or aperture, 12, between the proximate knife edges of the cheeks around over the upper side ofthe member, 1, to the teeth ofthe comb which stops the groove. Obviously, it is immaterial whether the comb is at the upper or lower edge of the bar; that is, whether the operative portion of the grooves is at the lower or upper side of the rotary member. The duct bar, 5, has apertures, 5", in staggered arrangement in two rows corresponding in position longitudinally of the duct bar with the grooves of the rotary member, or, more exactly, corresponding with the position of the teeth of the comb or rack, 10, so that each roove stopped by a tooth of the comb or rac( registers y virtue of the engagement of the tooth in the groove with a duct openingl in the duct bar. These duct openings are fitted with nipples, 15, for the attachment of tubes, 15", leading to the operating devices of the pneumatic action, which is not shown. Upon considering this structure, it will be seen that by rotating the member, 1, the duct bar will be fed longitudinally by the engagement of the comb with the screw threads of the rotary member, each complete turn of the rotary member shifting the duct bar the distance from thread to thread. It will be observed, also, that in this process, each duct mouth will be moved relatively to the note-sheet apertures and transversely of the travel of the Ynotesheet, and that such movement may be utilized to correct the alinement of the duct mouths with the apertures; but it will be observed that each complete revolution of the rotary member, while passing the duct mouth transversely across the aperture of the note sheet will bring each duct mouth back int-o registration with the same aperture with which it was registered at the commencement of the revolution; but that, in the meantime, by the revolution, the duct or tube which connects with said aperture will have been changed and the next adjacent duct will have been brought into such regis tration. The device therefore operates perfectly, both for correction of alinement'and for transposition.

In order to render the ducts suitably airtight,--that is, to prevent leakage from one .to another, it is considered desirable that the cheeks, 3, 8, and the duct bar, 4, should have their faces which seat upon the rotary member felt lined; and since the movement of the screw threads on the felt lining which provide for relaxing the pressure of the y cheeks and duct board ,upon the screw threads; and this may be carried to the extent of taking said parts entirely out of contact with the rotary member while it is being rotated. For this purpose, the duct bar is made slightly Wedge-shaped or tapering in cross-section, and the rear portions of the cheeks, 3, between which the duct bar is embraced, have their faces which seat upon the duct bar slightly converging as already described. The duct bar being mounted for movement foreand-aft,-that is, toward and from the rotary member,-is connected for such movement with a rock shaft, 16, having an offset portion or crank wrist, 16, which engageseyes, 17, in brackets, 17, secured at the opposite ends of the duct bar so that the rocking of the shaft through a moderate angle moves the duct bar a. short distance toward and from the rotary member, 1, causing it in moving away from said member to wedge apart the cheeks, 3, taking them also away from that member, leaving it free for rotation. A tin er lever,l20, on t-he rock shaft, 16, serves or rocking the shaft, as described, to draw the duct bar away from the rotary member. The relative direction of the several crank wrists of the rock shaft, 16, is such that when the finger lever, 20, is depressed by the operator, the crank wrist or offset portion, 16, is carried around to the dead center point so that it automatically locks the parts in position withdrawn from the rotary member, retaining them thus while the operator rotates the said rotary member through any desired number of turns fox` transposition; whereupon the finger lever being lifted, the parts will return to their working position as above described.

I claim 1. A tracker device for automatic musical instruments comprising a rotary member having a continuous screw thread, two members which snugly embrace the rotary member extending longitudinally thereof and having longitudinal edges slightly spaced apart crossing the threads of the rotary member and together therewith bounding the mouths of ducts formed by the threads; a duct bar embraced between the two members at the opposite side of the rotary member from said spaced edges of the embracing members and with its inner face bearing against the rotary member; a rack or comb on said duct bar having its teeth snugly engaging the threads of the rotary member, said duct bar having duet apertures which at the inner surface of said bar are respectively alined transversely thereof with the rack teeth, .and means for rotating the rotary member.

2. In a tracker device in combination with a back or base board, bearings projecting therefrom; a rotary member having a continuous screw thread and mo-unted for rotation in said bearings and means for rotating it therein, the back or base board being apertured longitudinally of the rotary member opposite the same; a duct bar protruding into said aperture and mounted for movement therein longitudinally of the rotary member with its inner face bearing thereagainst; a rack or comb on said duct bar having its teeth engaging snugly the screw threads of the rotary member; two cheek pieces embracing snugly the rotary member and said duct bar having longitudinal edges oppositel the duct bar slightly spaced apartcrossing the threads of the rotary member,

coperating therewith to form tracker duct mouths.

3. A tracker device comprising a back or base board, bearings extending therefrom; a rotary member journaled in such bearings having a continuous screw thread and means for rotating such member, the back or base board being apertured longitudinally of the rotary member opposite the same; a duct bar protruding'through and movable longitudinally in such aperture into Contact with the rotary member having a. longitudinally extending rack whose teeth snugly engage the screw threads of the rotary member; two cheeks which snugly embrace the duct bar and the rotary member having their longitudinal edges opposite the duct bar slightly spaced apart forming a rift crossing the threads of the rotary member and cooperating therewith to bound themouths of tracker ducts formed between the thread, the

duct bar having duct apertures extending through it and at the inner surface of the bar alined respectively with the rack teeth; spring-pressed means which hold the cheeks yieldingly toward each other for embracing the duct bar and rotary member, the proximate faces of the cheeks which embrace the duct bar being converging away from the rotary member in plane transverse thereto, the duct bar being correspondingly Wedgeshaped; means for forcing the duct bar away from the rotary member to wedge the cheeks apart7 and means for rotating the rotary member while the cheeks are thus separated.

4. A tracker device for automatic musical instruments comprising a rotary member having a continuous screw-thread; members Which snugly embrace the rotary member extending longitudinally thereof, having longitudinal knife-edges slightly spaced apart crossing the threads of the rotary member and substantially7 tangential thereto and together bounding the mout-hs of ducts formed by the threads; a duct bar embraced between the two members which embrace the rotary member at the opposite side of the rotary member from said knife edges; a rack or comb on said duct bar having its teeth snugly engaging the threads of the rotary member, said duct 'bar having duct apertures which at the inner surface of said bar are respectively .alined transversely thereof with the rack teeth, and means for rotating the rotary member.

In testimony whereof, I have hereunto set my hand, at Chicago, Illinois, this 30th day of December, 1910.

CHARLES S. BURTON.

Witnesses:

EDWARD T. WRAY, M. GERTRUDE ADY. 

